How to change bg color in Google Maps' balloon (infowindow)?

Hello!

There're zillions of articles about it, but almost nothing is a simple and step-by-step guide. Somehow I managed to figure out most of functions of Googlemaps Plugin (Joomla extension). What I got you can see here:

http://repetitorov.com/contact

Here's the code that I use:

{mosmap text='<div style="text-align:center"><b>Наш адрес:</b>
71252, г. Тель-Авив,
ул. Арлозоров 225-Б,
2-й этаж, офис 25
<a href="http://www.kotkovski.com"=linkTarget title="На главную">www.kotkovski.com</a>

<img src="http://www.repetitorov.com/images/contactformTA1.png" width="283″ height="250″ />'}

It's all nice...but I can't figure out how to change background color of the balloon (infowindow) from #fff to #ebf3fb (it's a color of page's sheet to match it better).
I don't care whether it's a JS or a CSS-based solution, as long as it's easy to implement in Joomla!.

The weirdest part is that when I open Firebug, it shows that the lowest part in the middle of the balloon (the one that connects the balloon to the marker) doesn't belong to the same div style!